Most of us speed, because there's only a small (maybe
1/1000) chance of getting caught on any one occasion.

Many of the same people buy lottery tickets because there is
a small (1/1000,000) chance of winning on any one occasion.

Putting these two facts together, it's clear
that speed
cameras work the wrong way around.

Instead of the current system, speed cameras should detect
people travelling at or below the speed limit and, one time in
a million or so, that person (identified by their number plate)
would win a significant sum of money.

Bakedhttp://www.wired.co...ivers-to-slow-down/This is an oft-cited example of 'gamification'. Fines are collected from people over the speed limit and then paid out in a lottery to people who drive under the speed limit. [hippo, Apr 07 2015]

One possible revision. At least in the US, people
get really itchy about being tracked. A speed
camera that takes a picture when someone is
detected to most likely be breaking the law is one
thing. A camera that photographs everyone who
isn't breaking the law to put them in a drawing
might make people worry about abuse of the
system. As an alternative, the cameras might be
designed so they normally don't take pictures, but
based on a low probability random number
generator will occasionally take one for the
lottery. Alternately cops on patrol could take
photos of people who appear to be driving safely.

Though I would worry some about corruption.
Need to ensure that everyone has a fair chance.

Maybe just aim at being revenue neutral. I think his
idea would be effective for getting many people
who drive over the limit to drive a the limit, but we
still need to give tickets foe people who drive
excessively fast or that will become common. If all
the funds from tickets was distributed via the non-
speeding lottery it would have the side benefit of
eliminating accusations of police departments giving
tickets for revenue generating purposes.

This is a truly brilliant idea.
Think of all the time not wasted in arguments and court trials about speeding. Also reward is a much better motivator than punishment. So the effect might be dramatic. Keep a few speed traps, though, for the hard-boiled adrenaline freaks.
Where else could this principle be applied? - Thank you for not carrying spray color cans for your unwanted graffiti? - You are the 5.000th customer of our shop not caught lifting a pack of chewing gum. Congratulations. ---
Some time ago I ran into a speed trap. After an hour of consciously avoiding going over the limit, I thought of something else, and bam! I deemed this highly unjust, given my prior behaviour. It would have mollified me if I at least had the chance to offset the speeding ticket with the non-speeding gratification. -- Maybe Steven Levitt and his Freakonomics team could get a grant for a test run of this idea.

In some places, it is mandatory to put up signs
warning motorists of speed cameras, which sort of
defeats their object.

However, if the camera gave a reward instead of a
penalty, it might not be necessary to show their
locations. In that case, lots of mobile cameras could
move around day by day, so that motorists would
always be in fear of missing their chance to get rich.

That would work. In fact, it could be a net-loss game
for the drivers (just as the lottery is a net-loss game),
with only part of the penalty revenue going into
prizes. The underlying psychology is that people
value positive opportunities (a very remote chance of
winning) more than they fear negative opportunities
(a small chance of getting a penalty).